It is common commercial practice to include amylases in detergent compositions to enhance cleaning performance.
Indeed, amylase enzymes have long been recognised in dishwashing, hard surface cleaning and laundry compositions to provide the removal of starchy food residues or starchy films from dishware, flatware, glasses and hard surfaces or to provide cleaning performance on starchy soils as well as other soils typically encountered in laundry applications.
WO94/02597, Novo Nordisk A/S published Feb. 3, 1994, describes cleaning compositions which incorporate mutant amylases. See also WO/94/18314, Genencor, published Aug. 18, 1994 and WO/95/10603, Novo Nordisk A/S, published Apr. 20, 1995. Other amylases known for use in cleaning compositions include both .alpha.- and .beta.-amylases. .alpha.-Amylases are known in the art and include those disclosed in U.S. Pat. No. 5,003,257; EP 252,666; WO/91/00353; FR 2,676,456; EP 285,123; EP 525,610; EP 368,341; and British Patent specification no. 1,296,839 (Novo).
Moreover, proteases are commonly used in detergent composition were high sudsing and/or good insoluble substrate removal are desired. Indeed, their ability to hydrolyse proteins has been taken advantage of by incorporating naturally occuring and protein engineered proteases as an additive to hard surfaces cleaners, dishwashing compositions, laundry compositions and the like. Many stains are proteinaceous and wide-specificity proteases can substantially improve removal of such stains.
Therefore, while amylase is known to act on starch stains, there remains a substantial technical challenge in formulating detergent compositions comprising amylase and protease in such a manner to meet the consumer's need for superior cleaning performance on soils and in particular, starchy soils.
It is an object of the present invention to provide detergent compositions including laundry, dishwashing and hard surface cleaner, containing oxidative stability-enhanced amylases and specific proteases.
It is a further objective to formulate laundry detergent compositions which provide effective and efficient surface cleaning of textile, particularly on dingy stains.
It has now surprisingly been found that specific proteases at a level from 0.0001% to 0.5%, preferably from 0.001% to 0.2%, more preferably from 0.005% to 0.1% pure enzyme by weight of total composition provide a performance boosting function for the amylase enzyme. It is indeed believed that the enzymatic hydrolysis of the starch enhance the release of the proteinaceous compounds while the hydrolysis of the intertangled proteins stains helps the release of the starch components.
These benefits may allow either improved performance or a reduction of the detergent actives levels without associated performance loss.